Color derives from the spectrum of light (distribution of light energy versus wavelength) interacting in the eye with the spectral sensitivities of the light receptors. Color categories and physical specifications of color are also associated with objects, materials, light sources, etc., based on their physical properties such as light absorption, reflection, or emission spectra. By defining a color space, colors can be identified numerically by their coordinates.

Exploratorium neuroscientist Richard Brown discusses how we see color, how color vision evolved, why color vision varies from person to person, and how the scientific understanding of color vision has led to technologies such as color photography

Webcasts made possible through
the generosity of the Gordon and Betty Moore Foundation, The Jim Clark
Endowment for Internet Education, the McBean Family Foundation,.and the Corporation for Educational Networks Initiatives in California (CENIC).